@lmbart 

RE: However, I would expect it to be the opposite. Isn't the "original hired date" the first date a person was originally hired the first time and the "hire date" the date they rehired? Need clarification.

Yes, that is correct. The Original Hire Date is an HR concept that represents the first time the employee was hired, used in some HR reporting. The Hire Date is the most recent hire date, the re-hire date. You should be able to change both dates at any time, either to fix them, or when the employee is re-hired after their original hire date.